A spray tower (or spray column or spray chamber) is a gas-liquid contactor used to achieve mass and heat transfer between a continuous gas phase (that can contain dispersed solid particles) and a dispersed liquid phase. It consists of an empty cylindrical vessel made of steel or plastic, and nozzles that spray liquid into the vessel. The inlet gas stream usually enters at the bottom of the tower and moves upward, while the liquid is sprayed downward from one or more levels. This flow of inlet gas and liquid in opposite directions is called countercurrent flow. Overview This type of technology can be used for example as a wet scrubber for air pollution control. Countercurrent flow exposes the outlet gas with the lowest pollutant concentration to the freshest scrubbing liquid. Many nozzles are placed across the tower at different heights to spray all of the gas as it moves up through the tower. The reason for using many nozzles is to maximize the number of fine droplets impacting the pollutant particles and to provide a large surface area for absorbing gas. Theoretically, the smaller...

The Battle of Verdun (French: Bataille de Verdun [bataj də vɛʁdœ̃]; German: Schlacht um Verdun [ʃlaxt ʔʊm ˈvɛɐ̯dœ̃]) was fought from 21 February to 18 December 1916 on the Western Front in France. The battle was the longest of the First World War and took place on the hills north of Verdun-sur-Meuse. The German 5th Army attacked the defences of the Fortified Region of Verdun (RFV, Région Fortifiée de Verdun) and those of the French Second Army on the right (east) bank of the Meuse. Using the experience of the Second Battle of Champagne in 1915, the Germans planned to capture the Meuse Heights, an excellent defensive position, with good observation for artillery-fire on Verdun. The Germans hoped that the French would commit their strategic reserve to recapture the position and suffer catastrophic losses at little cost to...

The 10th edition of Systema Naturae is a book written by Swedish naturalist Carl Linnaeus and published in two volumes in 1758 and 1759, which marks the starting point of zoological nomenclature. In it, Linnaeus introduced binomial nomenclature for animals, something he had already done for plants in his 1753 publication of Species Plantarum. Starting point Before 1758, most biological catalogues had used polynomial names for the taxa included, including earlier editions of Systema Naturae. The first work to consistently apply binomial nomenclature across the animal kingdom was the 10th edition of Systema Naturae. The International Commission on Zoological Nomenclature therefore chose 1 January 1758 as the "starting point" for zoological nomenclature, and asserted that the 10th edition of Systema Naturae was to be treated as if published on that date. Names published before that date are unavailable, even if they would otherwise satisfy the rules. The only work which takes priority over the 10th edition is Carl Alexander Clerck's Svenska...